Trifluoroiodomethane as a Precursor to High Global Warming Potential Climate Pollutants: Could the Transformation of Climatically Benign CF3I into Potent Greenhouse Gases Significantly Increase Refrigerant-Related Greenhouse Gas Emissions?

The transition away from the production and consumptionof highglobal warming potential (GWP) hydrofluorocarbons (HFCs) under the2016 Kigali Amendment to the Montreal Protocol on Substances thatDeplete the Ozone Layer (Montreal Protocol) has prompted air conditioning,refrigeration, and heat pump equipment manufacturers to seek alternativerefrigerants with lower direct climate impacts. Additional factorsaffecting alternative refrigerant choice include safety (i.e., flammabilityand toxicity), environmental, and thermodynamic constraints. At thesame time, manufacturers are incentivized to seek refrigerants withhigher energy efficiency, which saves on electricity costs and reducesindirect greenhouse gas emissions from electricity generation. Thelife cycle climate performance (LCCP) metric is commonly used to assessthe combined direct and indirect climate impacts of refrigerant-useequipment. Here, we consider an additional impact on climate performance:the degradation of refrigerant in equipment, i.e., the direct climateimpacts of high-GWP byproducts that can form as the result of addingtrifluoroiodomethane (CF3I) to refrigerant blends to reduceflammability. Such a production of high-GWP gases could change theacceptability of CF3I-containing refrigerants. Further,it highlights the need to understand refrigerant degradation withinequipment in calculations of the environmental acceptability of newcooling technology. Minimal researchhas been published to date on the climateimpacts of breakdown products of refrigerants containing CF3I. This perspective makes the case that the potential for creationand emissions of high global warming potential chemicals from thebreakdown of CF3I used as a refrigerant warrants furtherstudy.